The invention relates to a quick-change attachment to connect a tool, preferably to the boom of a hydraulic excavator, comprising a boom-connecting quick-change component to accommodate a tool, one end of which has a pin, and the other end of which is retained in a bearing of the quick-change attachment by positive-fit or friction engagement.
Quick-change attachments of the above type are widely used on hydraulic excavators and other construction machinery since they provide for the simple and rapid exchange of various tools such as hydraulic grabs, digging-excavating buckets, grapplers, or the like.
This species of quick-change attachments, which are used principally on construction sites, are constantly exposed to dirt and other hard loads—with the result that the bearings, principally the semi-enclosed portions of the quick-change attachment, are subject to significant wear. In order to ensure the full functionality of quick-change attachment systems, the bearing must be regenerated after a certain level of bearing play has been reached. This regeneration is usually accomplished by welding-based hard-facing of the region of the bearing, and by re-boring the bearing in a horizontal boring machine. The result is an extended out-of-service period and considerable expense since this work is performed only by special shops.